docs: def InsertMessage(self, message, timeout=None):
      """Inserts a message into the Fleetspeak server.
  
      Sets message.source, if unset.
  
      Args:
        message: common_pb2.Message
          The message to send.
  
        timeout: How many seconds to try for.
  
      Raises:
        grpc.RpcError: if the RPC fails.
        InvalidArgument: if message is not a common_pb2.Message.
      """
      if not isinstance(message, common_pb2.Message):
        raise InvalidArgument("Attempt to send unexpected message type: %s" %
                              message.__class__.__name__)
  
      if not message.HasField("source"):
        message.source.service_name = self._service_name
  
      # Sometimes GRPC reports failure, even though the call succeeded. To prevent
      # retry logic from creating duplicate messages we fix the message_id.
      if not message.message_id:
        message.message_id = os.urandom(32)
  
      return self._RetryLoop(
          lambda t: self._stub.InsertMessage(message, timeout=t))